Revert[8] "replace SkXfermode obj with SkBlendMode enum in paints"

src/effects/SkLightingImageFilter.cpp

Index: src/effects/SkLightingImageFilter.cpp
diff --git a/src/effects/SkLightingImageFilter.cpp b/src/effects/SkLightingImageFilter.cpp
index 56275743d75d9a18cdec4075698671cc58abb99f..057ef24e95d8f4109d0a796b01e3d0801aa2c256 100644
--- a/src/effects/SkLightingImageFilter.cpp
+++ b/src/effects/SkLightingImageFilter.cpp
@@ -396,7 +396,7 @@ void SkLightingImageFilterInternal::drawRect(GrDrawContext* drawContext,
     sk_sp<GrFragmentProcessor> fp(this->makeFragmentProcessor(src, matrix, srcBounds,
                                                               boundaryMode));
     paint.addColorFragmentProcessor(std::move(fp));
-    paint.setPorterDuffXPFactory(SkXfermode::kSrc_Mode);
+    paint.setPorterDuffXPFactory(SkBlendMode::kSrc);
     drawContext->fillRectToRect(clip, paint, SkMatrix::I(), dstRect, srcRect);
 }